Transgenic potato (Solanum tuberosum L.) lines of two cultivars, Ilam Hardy and Iwa, were developed using Agrobacterium-mediated transformation to transfer a cry1Ac9 gene under the transcriptional control of the CaMV 35S promoter. PCR confirmed the presence of the nptII selectable marker gene in all recovered lines. All ten lines of Ilam Hardy and 14 of 15 Iwa lines were PCR-positive for the cry gene. In greenhouse trials, all Ilam Hardy transgenic lines produced phenotypically normal plants and significantly inhibited larval growth of potato tuber moth (Phthorimaea operculella Zeller). In contrast, only 60% of the Iwa transgenic lines produced phenotypically normal plants, but all lines positive for the cry gene significantly inhibited larval growth. All transgenic lines with a greenhouse appearance equivalent to the nontransgenic controls and improved resistance to potato tuber moth larvae were planted in the field. Three of the ten Ilam Hardy lines and two of the eight Iwa lines retained phenotypically normal appearance in the field and produced tuber yields equivalent to the nontransgenic controls. All five of these transgenic lines significantly inhibited larval growth of potato tuber moth on excised field-grown leaves. A high correlation was established between larval growth indices from the greenhouse and the field. A transgenic line from each cultivar inhibited larval growth by over 40%, and the line derived from Ilam Hardy prevented pupation of all larvae. Southern analysis on these five elite lines revealed that they contained either one or two copies of the cry1Ac9 gene. The amount of Cry protein in all transgenic lines tested was less than 60 ng·g-1 of fresh leaf tissue. A transgenic line from each cultivar was identified with comparable phenotypic appearance and yield to their parent cultivars coupled with high resistance to PTM.

Transgenic onion plants (Allium cepa) tolerant to herbicides containing active ingredients glyphosate and phosphinothricin were recovered from immature embryos of open pollinated and hybrid parent onion lines at a maximum transformation frequency of 0.9%. Transformants of different onion cultivars, grown on different selective agents and confirmed by Southern analysis, thrived with no apparent ill effects when sprayed with the respective herbicides at double the recommended field dosage for weed eradication. This study demonstrates that the transformation process described previously can be used with different selective agents and is cultivar independent.

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Phthorimaea operculella (Zeller), potato tuber moth (PTM), is an important pest of potatoes. The larvae of this insect are difficult to control with insecticides because they mine into foliage and tubers. Seven potato cultivars were genetically engineered with a Bacillus thuringiensis cry1Ac9 gene to confer resistance to PTM larvae. Fifty-six transgenic lines were established in the field at Lincoln, Canterbury, as small plots of 10 plants along with replicate control plots of the same, but non-transgenic, cultivars. Fortyfour of the transgenic lines were phenotypically normal. Foliage excised from these plants was challenged with PTM larvae in the laboratory. All but one line inhibited larval growth compared to non-transgenic plants (P<0.05). For transgenic plants the growth indices of larvae fed field-grown foliage were similar to those fed greenhouse-grown foliage. Thirteen of the 43 resistant lines inhibited larval growth by ≥40% and produced tuber yields comparable to the non-transgenic plants.

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